ARP/4/ARP_LEARNSTOP_TRAP:OID [OID] ARP learning stopped because the memory usage reached
the threshold. (Slot index=[INTEGER], Threshold=[COUNTER]).
设备单板内存的占用率达到指定的阈值(单板内存重启阈值-1。例如,1G内存单板的内存重启阈值是90%,当单板内存占用率达到89%时,产生该告警;2G内存单板的内存重启阈值是95%,当单板内存占用率达到94%时,产生该告警)时,ARP停止学习。